Taking the central conceit of Serial and dropping it into a group fitness class, the Missing Richard Simmons podcast has become must-listen entertainment in recent weeks. Recounting filmmaker Dan Taberski’s attempts to coerce Simmons out of an apparently self-imposed three-year exile, the podcast has reinvigorated interest in the flamboyant fitness guru.

The final installment, which came out yesterday, did not answer every lingering question surrounding his seeming disappearance, but there’s still plenty of Simmons lore to pore over. Check out 12 things that may help you better understand the man behind the sequined tank tops.

1. HE WAS ALMOST FATHER SIMMONS.

Born in 1948, Simmons was raised in a very religious household in the French Quarter of New Orleans. After graduating from high school, he entered a Dominican seminary in Iowa and stayed for nearly two years before leaving. “It just wasn’t for me,” he said, citing his 240-pound frame that had been engorged on food addiction from an early age and his “loud” persona as being less than fitting for the job. Simmons also tried getting into medicine but found that “dead bodies [and] blood” were unnerving. He also had stints as a cosmetics executive and fashion illustrator before finding his niche in the fitness industry, opening the Anatomy Asylum exercise studio in 1975.

2. AN ANONYMOUS NOTE LED TO HIS BODY TRANSFORMATION.

According to a 1981 feature in The New York Times, Simmons was working as a “fat model” in Europe in 1968 when he found a handwritten note stuck to his car. “Fat people die young,” the paper read. “Please don’t die. Anonymous.” Rattled by the message, the then-268-pound Simmons developed an eating disorder, surviving on water and lettuce for more than two months. Eventually, he recovered and developed a new philosophy: "Love yourself, move your body and watch your portions."

3. HE APPEARED IN TWO FELLINI MOVIES.

Before Simmons slimmed down, he was enjoying the cuisine of Florence, Italy, where he was studying art in the late 1960s. While there, Simmons nabbed parts in two movies by acclaimed Italian filmmaker Federico Fellini: Satyricon and The Clowns. The footage is apparently the only existing evidence of his former frame: Simmons once said he “burned” all other photos prior to his weight loss.

4. HE REVOLUTIONIZED THE ‘80S FITNESS TAPE CRAZE.

No video store in the 1980s was complete without a section devoted to fitness. Industry stars like Jake Steinfeld and Tony Little shared shelf space with tapes from Jane Fonda and Arnold Schwarzenegger. In almost all of these releases, perfectly-proportioned motivators and models led viewers through rigorous workout routines. When Simmons started his Sweatin’ to the Oldies series in 1988, he elected to populate his stage with regular people who were still struggling with weight loss. Consumers appreciated that Simmons wasn’t holding them up to a fitness magazine ideal, and the Sweatin’ series went on to sell 25 million copies.

5. HE HAS BEEN KNOWN TO CONFRONT OVEREATERS.

Early in his mission to eliminate excess adipose tissue, Simmons admitted to confronting total strangers over some of their dietary choices. “I’ll see an overweight woman eating a butterscotch sundae,” he told People in 1981, “and I’ll sit at her table and say, ‘What is this?’” When he operated a trendy Los Angeles eatery he called Ruffage in 1975, he’d also sit down with his customers and tell them if they needed to lose weight.

6. HE ONCE REPLACED ALEX TREBEK.

In 1987, syndicated TV distributor Lorimar attempted to capitalize on the home-shopping craze with ValueTelevision, a one-hour show where viewers could place orders via the telephone for featured products. The series was co-hosted by Jeopardy! star Alex Trebek. When the ratings were less than Lorimar anticipated, they fired Trebek and replaced him with Simmons. Nothing seemed to work, and the show was canceled in June.

7. HE USED TO TOUR SHOPPING MALLS.

Beginning in 1979, Simmons appeared on the ABC soap opera General Hospital as a fitness instructor. With the cast, he began making personal appearances at shopping malls: Simmons was so impressed by the number of people he could reach this way that he continued even after leaving the show in the early 1980s. “I travel almost 300 days a year,” he said in 1991. “I do mostly shopping malls, because everyone will come to a shopping mall, no matter what they weigh, no matter their economic structure, no matter what they drive. The malls are the meeting places of America. And so that's where I go."

8. HE DOESN’T LIKE SARCASM.

In 2004, Simmons was at Phoenix’s Sky Harbor Airport when a fellow passenger made a caustic remark about his Sweatin’ to the Oldies series of tapes. According to police, the man spotted Simmons and shouted, “Hey, everybody, it’s Richard Simmons. Let’s drop our bags and rock to the ‘50s.” The heckling was unappreciated by Simmons, who reportedly walked over and slapped the man across the face. According to the Bangor Daily News, police cited him with misdemeanor assault. The case was later settled and dropped.

9. DAVID LETTERMAN GAVE HIM AN ASTHMA ATTACK.

Simmons was a frequent guest on David Letterman’s late-night talk shows, with Letterman often playing the straight man to the hyper antics of Simmons. In 2000, Simmons took a break from the appearances after Letterman playfully sprayed him with a fire extinguisher, prompting the asthmatic Simmons to have so much trouble breathing that paramedics were called. The normally affable Simmons was so upset by the incident that he refused to appear on the show for six years.

10. HE DOESN’T LIKE RESTAURANTS.

Speaking with the Denver Post in 2008, Simmons said that he very rarely visits restaurants owing to the fact that people can’t stop craning their necks to see what the diet guru has ordered. To maintain some semblance of privacy, Simmons typically gets room service while traveling. He also avoids grocery stores, citing concerns that people tend to call him over and ask him to read the ingredients label to see if it’s a healthy option.

11. HE CALLED HIS DOGS ON THE PHONE.

Describing himself as a “loner” who doesn’t have many friends, Simmons once revealed a strong emotional bond with his three Dalmatians he named after characters in Gone with the Wind. When traveling, Simmons said he would call his house and sing to them over the telephone.

12. HE FORESHADOWED HIS OWN EXIT IN 1981.

As his fame and success grew, Simmons became a fixture on television and in print. Speaking to People for a profile in November 1981, the fitness expert said he received 25,000 to 30,000 letters every day and tried to meet as many people who requested his help as possible. “The day I don’t love any of this,” he said, “I’ll walk away.”

All images courtesy of Getty Images.